Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound.
Bill morphology shifts along with fundamental frequency in urban birds: we talk a lot in ORCAA about the way animals change their vocalization in response to outside pressure, but there are physiological constraints on the changes that can be made (for example, there’s no way I can sing bass, although I can get to tenor if I warm up). Birds in urban, disturbed areas had longer, narrower bills, which might help them get food at feeders, but actually makes it harder for them to vocalize at the higher frequencies that are more advantageous in noisy areas.
40-million-year-old protowhale was sensitive to low frequency sound: I’m a little bit of a paleo-nerd, so this was pretty cool to see. They looked at CT scans of the inner ear structures of this fossil, Zygorhiza kochii, and compared it to current mysticetes, and found that they were similar, indicating Zygorhiza was probably also sensitive to low-frequency sound the way our current baleen whales are. This implies that the order developed with a sensitivity to low-frequency and toothed whales’ high-frequency sensitivity came later.
Baird’s beaked whales are affected by sonar: beaked whales are some of the most mysterious ocean-dwellers, and we know little about their life history, behavior, or response to noise. Using acoustic tags, these researchers found that a Baird’s beaked whale displayed unusual diving behavior after being exposed to sonar.
Fun link of the week: I’m taking next week off because it’s the day before Thanksgiving here, and I’ll be traveling and then spending four straight days eating my family’s amazing cooking. So this week I give you a video about turkey vocalizations! Bonus: if you have energy, a paper cup, some string, and a paperclip after gorging yourselves on turkey, you can make a simple turkey-ish call.
Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound. Lots of birds this week, it turns out!
Humans and hermit thrushes show convergent “song cultures”: this is a cool one, and a little complicated. Apparently people have long debated the human preference for simple integer harmonics in our music–these are what generate our scales, both Western and non-Western. It turns out that hermit thrushes also prefer simple integer harmonics, and it’s actively selected for. While this isn’t prevalent among all birdsong, it’s interesting to see that there’s a sort of convergent evolution of this “song culture”!
Birds are impacted by road noise on their autumnal migration routes: a lot of work has been done on birds in springtime (since that’s when mating tends to happen), but these researchers found that birds also prefer quieter areas on their autumnal migration route too. Unless they’re insectivores, in which case they didn’t care.
Fun link of the weekis courtesy of Holger again, who is finding the best stuff on the interwebs. Did you know that the European Space Agency just landed a spacecraft on a comet?!? SO COOL! Here’s another thing I didn’t know: comets sing!! Follow the link and you can hear a comet singing!
Before I went to ASA last week, I had this grand idea that I would do a sort of journal-blog thing, where I’d periodically write little snippets about what was going on and how I was feeling. I started off really well, too, but all of it basically went out the window when Holger came to pick me up Sunday morning.
Let me preface this post by saying that most of the other members of ORCAA have been to a big conference before, including this one last year. This was my first—I had given poster presentations at small symposia, but nothing like this. It was also my first proper presentation.
The first thing you have to realize about ASA is that it’s the Acoustical Society of America. This means that any field that has anything to do with acoustics is invited. Biomedical acoustics, architectural acoustics, musical acoustics…these are just a few of the technical committees represented at this conference. It’s overwhelming. Mostly I hung around with the Animal Bioacoustics crew, which of course makes sense—this is most of what our lab does. I met tons of amazing people: other students, post-docs, researchers, professors. I even reconnected with several people from my old lab, the Cornell Bioacoustics Research Program.
My talk was on Monday, in the first session. I honestly don’t remember giving it, except for the point when my slides skipped too far ahead too quickly and when Niki dropped her cup and made me laugh. I was told it went well, though. I do remember answering questions, and feeling like I was able to respond to whatever was thrown at me without embarrassing myself. I even worked in a great response involving natural selection.
The nice thing about having your talk in the first session on the first day is that you have the rest of the conference to relax. The bad thing about having your talk in the first session on the first day is that people don’t always make it to see you. Many friends I made throughout the week didn’t get the chance to see me speak, and nor did one of the best connections I made during the week, Andrea Simmons. Andrea has been doing frog bioacoustics work at Brown for a long time, and I got to talk to her about both her work and mine on the last day I was there. She seemed very interested in what I’m doing, especially moving forward with the work I’m planning for my Ph.D. She also wants to come out and record our invasive bullfrogs with her array!
There were so many amazing talks given by tons of amazing researchers. I learned about horseshoe bats and their weird head movements. I learned about greater prairie chicken vocalizations. I even learned about frog-biting midges that are attracted to their prey through mating calls! And oh, the things people are doing with marine mammals! Marine mammal researchers get the coolest toys, I swear. Arrays and tags and three-dimensional plots of dives…so cool!
The entire experience was overwhelming, intense, and immensely gratifying. I felt humbled to be a part of such an amazing group of researchers, and proud and grateful to be welcomed among them. You only get one first big conference, and I like to think I nailed this one.
I’ve made a Storify of my tweets and others from the conference that you can see here. There was a budding and tight-knit social media presence at the meeting this year, which was great to see; a lot of the friends I made were made through Twitter! Other awesome ASA Storify collections can be found here by Ben Taft, and here by Will Slaton (two of my fellow live-tweeters).
In the midst of the summer and early fall when I was traveling a bunch and doing field work, I remember thinking how nice the term would be to be in one place for a while and get some analysis/other work done. What I didn’t realize was how unexciting my life would be for blog posts….
I guess excitement depends on your interests, though, because for me there have been SOME exciting moments standing in front of my computer. I’ve spent the last month putting my master’s on hold, instead analyzing acoustic data collected from one of our gliders that was deployed back in March, and then deploying and analyzing another glider all within the month of October. Want to see what I found? Good. I was going to put in the images anyway.
Here’s a Stejneger’s beaked whale click. The top image is a long term spectrogram, or LTSA, that shows 15 minutes. All the little bits around 50 kHz are beaked whale clicks. The middle spectrogram just shows one click during a fraction of a second, and the bottom shows the wave form, or the amplitude of the click.
From the March deployment, the excitement came in the form of TONS of beaked whales. Like so many. Like all the time. Including the super weird looking Stejneger’s beaked whale (Mesoplodon stejnegeri). I can tell the species by what frequency the click is at, how much time there is between clicks (inter click interval, aka ICI fyi), and the duration of the click. They are all unique features for this species of beaked whale, which I know thanks to other people confirming that by combining visual and acoustic data like was done by theses lovely folks at Scripps.
Here’s two porpoise species detected together – harbor porpoise (the two higher frequency red specs) and Dall’s porpoise (the middle, slightly lower frequency). All together a bunch of those clicks make up that light blue section in the LTSA on the top.
The March deployment also brought excitement through porpoise recordings! Did I mention that glider was the first of its kind to record ultra high frequencies? We used a 394 kHz sampling rate, which means we could detect vocalizations up to 196 kHz, which is where porpoise and a few other odontocetes (toothed whales) vocalize. Most equipment doesn’t sample that high (memory gets filled too fast) so this was pretty neat-o. I’m a big fan of looking for these ultra high frequency encounters because they are so obvious in the upper part of the LTSA, far above the background noise.
And like I mentioned, I did go out in the field one day. We deployed one of our new gliders for a few days just outside of Newport in early October, and I went out on the recovery. I took this one super exciting picture of these gulls on the back of the ship. You’re welcome.
Piper helped Holger and Alex prep Will the glider before he got deployed in early October.These gulls agree with “no excitement November”. Until I threw pistachio shells over the side. Sadly this is the only picture I took of the whole glider recovery.
Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound. Welcome to November, everyone! Fall is definitely here! I promise I’ll have a proper ASA post up soon, but in the meantime here are your Soundbites for the week!
Cruise ships may be having an impact in developing tourist markets: the good thing about ecotourism is that you’re not openly depleting resources the way you used to be. The bad thing about ecotourism is that increased exposure can degrade the environment. Places like the Eastern Mediterranean and the Adriatic are facing increased noise levels because of increasing tourism.
Microclimate affects frog calls: abiotic noise like streams and waterfalls can have as much of an impact on vocalizing animals as anthropogenic noise. Here the researchers wanted to know if frogs in different microclimates (near stream, far from stream) were changing their call frequency to overcome stream noise, and they were!
Fun link of the weekthis week comes from Holger and Radiolab–the story of a vest that helps deaf people hear.
Although I won’t be formally joining the lab until January, my informal transition has already begun. Luckily for me, my tenure at as graduate student started off with a fieldwork cruise! In September I joined the crew of the Bell M. Shimada to assist with the deployment of one of ORCAAlab’s Ocean Noise Reference Station (NRS) moorings. The focus of my graduate research will be to analyze recordings from the NRS project, so it was exciting to have the opportunity to help out with a deployment.
This is a map of the NRS deployments. On the Shimada I helped deploy NRS03.
The Ocean Noise Reference Stations will be deployed in NOAA Marine Sanctuaries and some other US marine areas of interest. We hope that the recordings from these moorings will allow us to compare ocean soundscapes and monitor long-term changes in a new way. Currently, many different types of autonomous recording units (ARU) exist and are used by passive acoustics research groups. While this is excellent for documenting ocean noise in isolated areas, different recording technology and mooring design make it difficult to compare soundscapes. The NRS project recorders are all calibrated to the exact same specifications so we may accurately compare ambient ocean noise around the US and in NOAA sanctuary waters.
NRS03 staged on the deck.
On this trip we were to deploy NRS station 3, off the coast of Washington State. We set sail out of Newport on a wet and windy day. This was my first journey in the Pacific ocean, and the weather certainly lived up to my expectations! Avoiding the offshore storms, we started our trip by traveling north along the coast of Oregon. Cheif scientist Jay Peterson recruited a science crew of faculty, students, and volunteers and we were all assigned watches and jobs for our week on the Shimada. Between all of us we would process water samples (via CTD), jig for squid, dip-net for jellyfish, retrieve a NOAA DART (Deep-ocean Assesment and Reporting of Tsunamis) monitoring buoy, and deploy a Noise Reference Station. Suffice to say, we had a busy week at sea!
Preparing the float for deployment (photo credit: Megan Stachura) .Deploying the top float of NRS03.
I was also able to help out with some of the other projects. Here I am helping to catch jellyfish for Samantha Zeman’s project.
Trying to catch jellyfish in the dip net (photo credit: Megan Stachura) .We came across a swarm of jellyfish on out way back into Newport (photo credit: Megan Stachura).
It was great to have the opportunity to visit Newport before starting at OSU this winter, and I hope I get a chance to help with another deployment soon!
Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound. I’ve been doing really well on this weekly thing, but I might break my streak next week as I’ll be in Indianapolis for ASA(!). That just means you’ll get a real blog post from me next week!
Aposematism led to increased vocal diversity in poison frogs: tip o’ the finder hat to my Garcia labmate Lindsey for this one, and it’s brilliant. You know those little brightly colored poisonous frogs? These authors wanted to know if aposematism (displaying bright colors like that as a warning to predators) might lead to increased vocal diversity, since they’d have to worry less about predation. And it did! In conjunction with sexual selection, aposematism allowed the evolution of a broader vocal repertoire!
Silvereyes shift their frequency down in urban noise–and it works: These are silvereyes. They’re really cute. You can find them in Australia and New Zealand (which is where I took this photo). Most animals shift their frequencies up above urban noise, but it turns out silvereyes shift theirs down. This increased the predicted effective space of their alarm call 20%!
Oscar Wilde said that “Conversation about the weather is the last refuge of the unimaginative.”
Sorry Oscar, despite my deep respect and admiration to you I will have to object this one.
Talking about the weather is lame; I seriously thought before. But I have changed my mind, since I moved to the Oregon Coast. Talking about the weather is lame at the cases that the weather is consistent, predictable and largely warm and sunny. This is not the case at the Pacific Northwest.
The variability of the weather at the Oregon Coast
I often find myself complaining about the weather (this is my version of talking about it) since I moved here, and now it’s time to better look into it. Without my usual pout when I curse the rain, or my frown when it’s sunny but really windy. I am not grumpy in reality; I am just a bicycle commuter. That means that I don’t have the choice of a well heated, or at least a dry seat at bike-unfriendly times. I am always exposed to the weather and it affects me every single day. I have been repeatedly soaked by the North Pacific rain and blown away by the Northerly winds (we name the winds from the direction that they come from) over and over again. Immediately when I arrived here I was warned about the horizontal rain that I had never heard of before and no umbrella could keep it off me. The wind is ruthless at the North Pacific.
The truth is that everyone is affected by the weather and has his/her own relationship with it depending on where they come from, what they are used too and how their internal thermostat is tuned, and also on their personality. If you come from Greece, the Oregon Coast will appear cold, whereas if you come from northern France (clear reference to one of my housemates) it will feel like home. If you are outgoing and social the warm sunny weather suits you and defines you. If you are more of an introvert the rain and the low temperatures will provide the right conditions for you to stay home and enjoy solitude.
Research shows that the weather and particularly the sun affect our mood. I clearly see more smiley faces in a sunny day, mine included. Studies indicate a link between low pressure and suicide. On rainy days people report lower satisfaction with their lives. Now imagine how challenging it can be to be a graduate student in a tiny town on the Oregon Coast…!
Overall, I think that the amount of energy that we receive from the huge flaming star on the sky defines who we are, and seems to be a driver of peoples cultures. I am certain that you also have noticed generic cultural differences among people that come from southern and northern regions in a global or even in a national scale. I might be judged for stereotyping but there is some truth to that.
There are 3 major factors why the weather is important for biologists-acousticians:
1. It is linked to food and everyone cares about food
The animals care about the weather! Their distribution is defined by the climate together with other parameters. The sperm whales for example, being truly cosmopolitan, are encountered in the most parts of the world’s seas from the equator to the edge of the polar ice. However they have their temperature preferences. The females like it warm and don’t go to temperatures lower than 15°C. While the groups of females and young males are thought to remain in lower latitudes year round, the macho adult males have wider physiological demands and are encountered in polar areas.
The sperm whales display a remarkable sexual dimorphism with the males being ~1.5 times longer than the females. The larger the size of the animal the more favorable is the surface-to-volume ratio. Even though they have a large surface area that they lose heat from, this area is small in relation to their heat-producing body mass. Thus the males can migrate to high latitudes, especially during summer months, to productive feeding grounds where they karaoke with my hydrophone located at the Gulf of Alaska.
Some enjoy field work more than others
Within their calls I am sure that whales talk about the weather too because highly productive spots are identified, like upwelling areas and other cool places where plenty of food is available and the animals tend to aggregate. Though, the precise process that links the environmental factors in the open ocean with the distribution and abundance of large predators is difficult to be determined and is a major goal of my research. Investigating the oceanographic parameters that affect the movements of sperm whale populations is a particularly complicated matter since they feed on deep sea creatures (bathypelagic squid) and the linkages of physical forcing (wind, temperature) with primary productivity and aggregations of prey and predators are temporally and spatially variable.
2. The sound in the ocean likes it hot
The propagation of sound in the oceans is largely affected by oceanographic variables (which are related to the weather) such as temperature, pressure and salinity. The speed that the sound travels underwater varies from area to area, season to season and different time in the day. Generally the sound speed increases when all the above variables increase. Since these variables change with the depth, the sound speed profile also changes with depth in the water column.
Temperature, Salinity and pressure ocean profiles at mid-latitudes
sound speed profile at mid latitudes
High sound velocity on the sea surface where the water gets warmed up by the sunlight decreases down to the depth where the water temperature becomes constant (~1000m) and then it starts increasing again when the pressure increase is dominant. At the transition point where the sound velocity reaches a minimum (~1000m) it is formed a sound channel where sound waves get trapped and propagate really far away. This is named as the SOFAR (SOund Fixing And Ranging) Channel and some species of whales find it to be very useful to communicate with their friends, partners, parents, cousins and aunts that are immigrants to faraway seas.
colorful figures with boats in them are always better
I use skype.
message to self: use SOFAR channel
Do remember this SOFAR chitchat when you decide to deploy your instrument to record whale voices and you cannot decide on the depth 😉
And to turn the talk-about-the-weather into a hot topic, consider what happens when climate change is introduced and the small talk becomes a conversation where personal ethics, political and social opinions are involved. More like loud talk now! Now that I said loud, did you wonder what is the effect of climate change to the sound propagation and consequently the whales’ communication, and you were afraid to ask?
Ocean acidification, the decrease of the pH in the seas, is a notorious climate change impact. This increase of the ocean acidity changes how sound travels underwater: the lower the pH (more acidic), the ocean absorbs less sound and the higher is the sound speed. And now you are thinking: “Voila, the whales can be heard even further now!”. However, the reality is less comforting (as usually). At the frequencies that the whales vocalize we make a whole lot of noise with shipping and naval activity, seismic exploration and other significant anthropogenic sound sources that interfere with the whales’ skype and consequent communication issues. Yep, ocean acidification makes the sound pollution in the seas into a magnified problem.
3. People love listening to the rain
Since the weather affects the ocean soundscape, then it can also be measured by the sound it makes! Rain and wind generate sound at the sea by producing bubbles during splashing at the ocean surface. These physical processes create different distribution of bubble sizes that have a different footprint on the soundscape. This way the sound from breaking waves (caused by the wind) can be distinguished from the rainfall sound and we are able to monitor the ocean surface conditions from below the surface. Huzzah, here is the solution to trying to measure wind speed and precipitation in difficult locations where the measured vicious weather elements can actually destroy the instruments that we use to measure them. The instrument that I use, the Passive Aquatic Listener (aka PAL) was originally designed by Dr. Jeffrey Nystuen to detect and measure rainfall and wind speed at sea. Lucky me, it works great with recording marine mammals too!
Weather and bubbles talk. This is so scientific.
By this point of this post I have been unnecessarily negative with the Oregon Coast weather which to be frank is what makes this corner of the world into a magical place. The northerly winds in the summer are the reason for the upwelling to take place and all the whales and other astounding marine life to move up this way for food. Seeing the whales from the beach or even just the balcony of your house is certainly worth suffering some cold winds. The world we live in is alive because of the winds. The wind is the breath and the heartbeat of the Earth. The rain on the other hand gives life to thriving and fairytale-like old-growth forests with splendidly diverse and abundant wildlife, fills the rivers and the lakes. Did I mention how outdoorsy I have become?
A question to you: do you also see an irony in the name “Pacific” or I am being grumpy again?
I am not grumpy at the Oregon Coast
Here it comes, a welcome wind: the wind of change. I am moving to the valley!
Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound.
High-frequency vessel noise may have an effect on marine mammals in shallow water: much of the anthropogenic noise that we’re concerned with at ORCAA, whether it’s road or vessel noise, is low-frequency because of the attenuation of higher frequencies. However, in shallow water, the high frequencies may not attenuate as much and may therefore cause masking for higher-pitched odontocetes.
Direct-developing frogs are more reliant on climate cues to start calling: what a week, we get one whale link and one frog link! There are some species of entirely terrestrial frogs that don’t go through a tadpole stage; instead, they hatch as mini adults. However, the eggs still need to be kept moist while they’re developing. These researchers found that the onset of calling was more closely tied to high humidity and rainfall than it was to overall air temperature, which is a different cue than most species of tadpole-metamorphosing frogs.
Fun link of the week: I’ve been practicing for my presentation at ASA in a couple of weeks, so I’ve been asking myself this question regularly: “does my voice really sound like that?” Here Greg Foot examines why our voices sound different on recordings.
Classes have started again here at OSU. I know this is old news for those east coast universities that start classes in late August or early September, but here in Ye Olde Oregon fall starts late… so school starts late. As a PhD student I’m no longer required to take classes at the university, and having just pushed the paperwork through on our National Park Service Grant I will soon be exclusively a GRA (graduate research assistant) and will no longer be required to teach courses either. For now, however, I am both student and teacher — taking classes and teaching them.
FW255 student James tests out the directional microphone during a playback study at Finley Wildlife Refuge.
I love teaching. Rare for many researchers I know, but for me – true. I find it helps me to synthesize my thoughts, to approach science creatively and simply, and to consistently reference back to the basics. In my tenure as a graduate student at OSU I’ve been privileged to both TA and instruct classes in basic biology, ecology, intro to anatomy, physiology and the disease, marine biology, marine mammal science, marine habitats, and (my all time favorite) field sampling. FW255 — field sampling — is a required course for all of our Fisheries and Wildlife undergraduate students; I’ve been a GTA (graduate teaching assistant) under the brilliant and compassionate guidance of biological oceanographer and community ecologist Dr. Doug Reese for four quarters. The course gives students the opportunity (under the instructors’ guidance) to design and execute field studies at the Finley Wildlife Refuge. Courses range from comparing predator habitat use, to investigating the impacts of beaver dams on water clarity, to chronicling avian community structure. I know. Our students are impressive, creative, young minds.
When your classroom looks like this… teaching is heavenly
For my part I see participating in this course as an opportunity to introduce undergraduate students to acoustic ecology. In my tenure I’ve guided students through studies that seek to aquatically detect amphibian species, investigate the impact of diel vs. nocturnal raptors on songbird communities, and studies that use acoustics (playbacks and recordings in this case) to test for territorial responses of red-winged blackbirds to encroaching yellow-headed blackbirds. Currently we’re starting up two playback studies; one study uses acoustic playbacks to investigate the impact of raptors on waterfowl, the other which will asses behavioral responses of elk to breeding calls (assuming we can find the elk — backup plan includes tracking elk and using trail cams. No student left behind here).
While there’s a lot to love about teaching this class (I spend two days a week hiking through a wildlife refuge looking for animals, I can pay my rent each month), there are a few things that really strike me as I start up my fourth quarter interacting with out students in the field. First, I have a lot to learn. Whenever I start to feel like I understand something in its entirety, be it about ecology or about bioacoustics, a student asks me a question I don’t know the answer to. I then go home, look it up, and learn something for the both of us. It is simultaneously refreshing, inspiring, and humbling. Good qualities for any PhD student to embody.
Second, teaching is valuable. While I believe that my research has, and will continue to have an impact of the world around me, when I teach I can see the impact. My students start the quarter not knowing how to do something (“What is a quadrat?”), perhaps lacking direction (a.k.a. don’t know how to operate a GPS), and are sometimes a little short in the inspiration department (“What study do you think I should do, Michelle?”), but when then leave? By the time my students hand in their final papers — a full scale research paper, intro, methods, results, & discussions, stats and all — I can see that they have changed (“We used a one square meter quadrat to investigate insect biodiversity between the upland forest and the agricultural lowland riparian zone”). Further, the relationships that I see unfolding in our class between the students and their groups, and the students and Doug and myself, are proof to me that doing science is a powerful tonic for a healthy life. Not everyone loves teaching, not everyone gets it, but for me (at least for now) it’s nourishing to put big picture impacts into real world perspective.
So yes, I am a teacher. Yes, I am a student. The teacher is a student & the students are the teachers.
But enough with philosophy (Niki’s really much better at that than I am). While 99% of the time I love teaching… no one can deny that this is also true. Cross your fingers and I may just graduate some day.
They’re really cute. You can find them in Australia and New Zealand (which is where I took this photo). Most animals shift their frequencies up above urban noise, but it turns out silvereyes shift theirs down. This increased the predicted effective space of their alarm call 20%!
